A New Scaleworm, Iphione malifera (Polychaeta: Iphionidae), 
from a Coral Reef in the Philippine Islands 
Christina N. Piotrowski 
Department of Invertebrate Zoology and Geology, California Academy of Sciences, 
55 Music Concourse Drive, San Francisco, California, USA 94118 
Email:cpiotrowsld@calacademy.org 
Anew species of scaleworm,//;/i/t7/i^ malifera, was collected from a shallow coral reef 
during the Hearst Philippines Biodiversity Expedition 2011. A morphological 
description is provided along with figures and comparisons are made with previous¬ 
ly described congeneric species. Iphione reticulata Amourtm., Rullier, and Fishelson, 
1978 is re-established as a valid species based on examination of the holotype. A key 
is provided to currently recognized Iphione species. 
It has long been acknowledged that the taxonomy and systematics of the Indo-Pacific poly- 
chaete fauna are in dire need of targeted study (Natividad and Palpal-Latoc 1986; Fauchald 1976). 
Despite recent recognition of the Coral Triangle biogeographic region as the “the global epicenter 
for marine biodiversity” (Barber 2009) and at least one study having demonstrated unusually high 
polychaete diversity in this region (Wallace et al. 2000), a relative dearth of taxonomic literature 
exist for its reef wonn fauna. This has led to the application of species names described from geo¬ 
graphically separate faunal regions, and has inhibited estimation of the extent of reef species yet to 
be described. One recently published study (Stella et al. 2011) indicated that approximately 8000 
coral-associated annelid species are known to occur in coral reef ecosystems. High incidence of 
cryptic and morphologically convergent polychaete taxa globally (Nygren 2013), coupled with a 
high rate of reported cosmopolitan species both globally (Glasby and Alvarez 1999) and from coral 
reef and other tropical environments (Fauchald 1976), have contributed to numerous erroneous 
reports of species distributed within the Indo-Pacific. Knox (1957) surveyed 212 published reports 
of polychaete species records in the Indo-Pacific and found some sub-regions with a proportion of 
“cosmopolitan” species as high as 40%. In this same study, an evaluation of 1,989 taxa reported for 
the Philippine Islands yielded 20% “cosmopolitan species”, whereas 36% of species examined 
were classified as endemic. Glasby and Alvarez (1999) pointed out that traditional assumptions 
regarding cosmopolitanism in this region have resulted from insufficiently resolved polychaete tax¬ 
onomy. Given our deficient taxonomic understanding of this frequently dominant faunal group 
within reef habitats (Klumpp et al. 1988; Grassle 1973), it is perhaps not surprising that even large, 
morphologically unique polychaete species remain undiscovered in near-shore Philippine coral 
reef systems. One such species of the scaleworm genus Iphione is described herein. 
Iphione is the only shallow water genus within the Iphionidae, a family recently resurrected 
and split from the highly speciose and paraphyletic family Polynoidae on the basis of compelling 
molecular evidence (Norlinder et al. 2012). Iphione superficially resemble chitons in their compact, 
stiffened appearance and exhibit convergent behavior to these armored mollusks, including com¬ 
parable defensive responses such as their tendency to clamp onto hard surfaces using muscular 
contraction, retraction of soft appendages under their protective scales, and a propensity to curl 
their bodies ventrally when distui'bed rather than attempting to swim in escape (Pettibone 1986; 
Storch 1967). In great contrast to chitons and like many other errant polychaete taxa, these carniv¬ 
orous annelids are equipped with an eversible pharynx anned with chitinous jaws and lateral para- 
podia from which bundles of chaetae arise. As with all other scalewonns (Aphroditoidea), iphion- 
ids are equipped with two longitudinally arranged rows of dorsal elytra. 
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